Role of Maillard Reaction Products as Antioxidants in Washed Cod and Washed Turkey Muscle Oxidized by Added Hemoglobin

Abstract

The ability of Maillard reaction products (MRPs) to inhibit hemoglobin (Hb)-mediated lipid oxidation is examined in washed cod muscle (WCM) and washed turkey breast muscle (WTM). Lipid peroxides and thiobarbituric acid reactive substances (TBARS) are used as markers of primary and secondary lipid oxidation products, respectively. MRPs inhibits Hb-mediated lipid oxidation in WCM (p < 0.01) but are weakly inhibitory in WTM. 𝜶-tocopherol concentration is 24-fold greater in WCM compared to WTM. The elevated 𝜶-tocopherol content of WCM may partly explain the enhanced antioxidant effectiveness of MRPs in WCM, noting that MRPs and 𝜶-tocopherol act synergistically in the scavenging of free radicals. MRPs are more effective in inhibiting lipid oxidation in WCM at pH 6.6 compared to lower pH values. Antioxidant effectiveness of MRPs diminishes when stored refrigerated but not with frozen storage. MRPs obtained by 3 h heating contains more Maillard reaction intermediates than 2 h heating, which better inhibits LOOH formation (p < 0.01). These intermediates decrease faster during refrigerated compared to frozen storage. These studies suggest elevated pH and sufficient endogenous tocopherols are required for low concentrations of MRPs to protect highly unsaturated lipid in washed muscle from oxidation by hemoglobin. Practical Applications: This study shows that the maillard reaction products (MRPs) can be used to inhibit the oxidation of tocopherol-rich meat products, and the MRPs stored in the frozen condition for a certain period also have antioxidant activity.

Divergent Reactivity of Hemoglobin Isoforms α2Aβ2 and α2Dβ2 from Meleagris gallopavo in Native and Fatty Acid-Modified States

“…Washed turkey breast muscle was prepared as defined by Liu . Turkey breast muscle (Jenni-O Turkey Store; Wilmar, MN) was denuded and ground through a 5 mm grinder plate (KitchenAid Food Grinder Attachment; KitchenAid, Benton Harbor, MI).…”

“…Isolation of free fatty acid (FFA)-modified metHb was performed based on the work of Wu and others. 5 Met-hemolysate (10 μM) was allowed to react with FFA (1 mM) in 10 mM phosphate, pH 7.4, in the presence of 0.1% Tween20 (v/v). The reaction volume was 50 mL and was allowed to proceed for 30 min at RT.…”

“…Excess Tween20 was then removed using a detergent removal spin column (Detergent-OUT Tween, Micro; G Biosciences, St. Louis, MO), according to the manufacturer's directions. Final concentrations (μM) of oxyHb, metHb, and hemichrome (Bis-His Hb) were calculated using the following equations 20 5 Turkey breast muscle (Jenni-O Turkey Store; Wilmar, MN) was denuded and ground through a 5 mm grinder plate (KitchenAid Food Grinder Attachment; KitchenAid, Benton Harbor, MI). Turkey breast mince was then combined with Milli-Q (18.2 MΩ•cm) water at a ratio of 1:3 (w/w) mince/water and mixed vigorously for 2 min.…”

“…Hemoglobin (Hb)-mediated lipid oxidation is a harmful phenomenon that affects the quality of muscle foods, as well as animal and human health. , Thus, understanding the structural and functional characteristics of various Hb isoforms, as they relate to redox status, is of significant interest. Considering the recent increase in poultry consumption worldwide and the relative susceptibility of turkey muscle foods to lipid oxidation in part due to endogenous, pro-oxidant, Hb, we aimed to understand functional characteristics of the coexpressed HbA and HbD isoforms from turkeys. The total Hb contents of turkey breast and thigh muscle are 0.16 and 1.02 mg/g, respectively .…”